JPH08331206A - Network managing system - Google Patents

Abstract

PURPOSE: To provide a network managing system with which the transmission reliability of Trap to be transmitted from equipment to be managed to a managing device can be secured without increasing the memory capacity of network constitutive equipment. CONSTITUTION: When the Trap transmitted from equipment 2 to be managed is received, a PDU concerning a specified managing object is transmitted to this equipment 2 to be managed by a Trap response processing part 16 provided at a managing device 1. Then, it is confirmed by a Trap response confirming part 27 provided at the equipment 2 to be managed whether the PDU from this managing device 1 is received within a fixed period from the transmission of Trap or not and when any PDU is not received, it can be grasped that the transmission of Trap is failed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network management system comprising a management device for network management using SNMP and a managed device managed using SNMP.

[0002]

2. Description of the Related Art Generally, a network management system using SNMP uses UDP on the fourth layer (transport) of the seven-layer reference model defined by the International Organization for Standardization (ISO).
(User Datagram Protocol), and a network management protocol, SNMP (Simple Network Man), is provided in an upper layer of UDP.
The device is managed by using the protocol stack on which the (agement Protocol) is mounted. The target of management is MI
B (Management Information)
A management object called "Base" is used, setting information unique to each device (device name, installation location, administrator, etc.), event count information (pattern reception count, error occurrence count, etc.), real-time status information (interface operation Information such as status) is included. UDP used in the transport layer does not send an acknowledgment to the system that sent it when it received the data. Therefore, U
The DP has a problem that even if data is not transmitted, it cannot be retransmitted, and reliability for transmission cannot be ensured.

In SNMP, each management device is managed by repeating the basic operation in which the management device requests the management device to retrieve / set management information and the management device responds to this request. is there. In addition, events (events) that are to be managed, such as failures, are displayed on the managed device.
When the event occurs, the managed device can notify the management device of the event content. In the SNMP, in order to perform the above operation, five types of PDUs (Protocol Data Un) transferred between the management device and the managed device.
it). That is, Trap, Get-Re
question, Get-Next-Request, Se
There are five types of PDUs, t-Request and Get-Response. Trap is a managed device
For example, it is for notifying the management device of the event contents when an event (event) to be managed such as a failure occurs. Get-Request is a request for the management apparatus to send management information to the managed device, and Get-Next-Request is a request for consecutively requesting different management information from the same managed device. . Set-Request is for the management device to request the managed device to change the object value of the MIB. In Get-Response, the managed device is Get-Request, Get-Next-R.
It is used when responding to the request and the Set-Request.

FIG. 3 is a block diagram showing an SNMP network management system. 1 is a management device, Tr
ap processing unit 11, Get-Response processing unit 1
2, Get-Request transmission unit 13, Get-Ne
xt-Request transmitter 14 and Set-Request
It includes an est transmission unit 15. Reference numeral 2 denotes a managed device, which includes a Trap transmission unit 21, a Get-Response transmission unit 22, a Get-Request processing unit 23, and a Get.
-Next-Request processing unit 24, Set-Re
It includes a quest processing unit 25 and a MIB 26. T
For example, when an event (event) to be managed such as a failure occurs, the rap transmission unit 21 sends Trap to the management device 1 to notify the management device 1 of the occurrence of the event to be managed. It is a notification. Trap processing unit 1
1 receives the Trap from the managed device 2 to recognize the occurrence of the event. Get-Request
The est transmitting unit 13 transmits Get-Request for requesting the managed device 2 to send management information, and is a Get-Next-Request.
The transmitter 14 is a Get-Next-Request for continuously requesting different management information from the same managed device 2.
It transmits st. The Get-Request processing unit 23 and the Get-Next-Request processing unit 24 retrieve the object value requested for the MIB 26 when receiving the Get-Request and the Get-Next-Request from the management device 1, respectively. To do. The Set-Request transmission unit 15 transmits the Set-Request for the management device 1 to request the managed device 2 to change the object value of the MIB 26, and the Set-Request processing unit 2
5 receives MIB2 when receiving Set-Request
Make changes to the 6 object values. Get-Re
The managed device 2 of the response transmission unit 22 is Get-R.
request, Get-Next-Request, S
Get-when responding to et-Request
Response is transmitted, and Get-Re is transmitted.
The response processing unit 12 receives the Get from the managed device 2.
-Responsive reception processing. MIB
The reference numeral 26 holds the management target.

As described above, in the network management system using SNMP, the Ge transmitted by the management device 1 is transmitted.
t-Request, Get-Next-Request
There is a response sequence in which the managed device 2 transmits Get-Response to the management device 1 with respect to three PDUs of t and Set-Request. However, the management device 1 that receives the Trap transmitted from the managed device 2 when the managed device 2 has an event to be managed does not respond to anything. further,
Since the UDP that does not ensure the reliability of the transmission of the transport layer is used, the conventional SNMP network management system has a problem that the reliability of the Trap transmission is insufficient.

In order to solve the above-mentioned problems, TCP (Transmission) is used in the transport layer.
Control Protocol)
It has been proposed to perform network management by P. In this case, since TCP performs confirmation response and retransmission for ensuring data transmission, reliability can also be ensured for the Trap transmitted from the managed device 2 to the management device 1.

[0007]

However, UDP
Since it is difficult to mix it with a general network device using TCP, it is difficult to shift to an SNMP network management system using TCP instead of UDP. Also, originally, it is desirable that the network device has a memory capacity as small as possible to make it smaller, but TCP is
There is a problem that the program becomes considerably complicated as compared with the DP and a memory having a considerably large capacity is required.

The present invention has been made in view of the above points, and an object of the present invention is to provide a Trap that a managed device transmits to a management apparatus without increasing the memory capacity of a network constituent device. It is to provide a network management system that can secure the transmission reliability of the.

[0009]

According to the first aspect of the present invention,
A management device that performs network management using SNMP,
It consists of a managed device managed using SNMP, and Tr when a managed device has an event to be managed.
In a network management system in which a PDU called “ap” is transmitted and the management apparatus receives the Trap to grasp the content of the event, the management apparatus receives the Trap transmitted from the managed device. A Trap response processing unit that transmits a PDU relating to a specific managed object to the managed device is added, and the managed device receives a PDU from the management device within a certain period after transmitting the Trap. It is characterized in that a Trap response confirmation unit for recognizing whether or not it is added is added.

According to a second aspect of the present invention, in the first aspect of the present invention, the Trap response confirmation unit of the managed device does not receive a PDU from the management apparatus within a certain period after transmitting the Trap. When it is recognized that the Trap is retransmitted, a Trap retransmission processing unit for retransmitting the Trap is added.

[0011]

According to the invention of claim 1, the Trap response processing unit provided in the management apparatus causes the PDU relating to the specific managed object to be transmitted to the managed apparatus when the Trap transmitted from the managed apparatus is received. To the device to be managed by the Trap response confirmation unit provided in the managed device.
PD from the management device within a certain period after sending Trap
It is possible to confirm whether U has been received, and if the PDU has not been received, it can be understood that the Trap transmission has failed.

According to the second aspect of the present invention, the first aspect is provided.
In the invention described above, Tra further provided in the managed device
By the p retransmission processing unit, the Trap response confirmation unit
If it is determined that the transmission of p has failed, the Tr
The ap is retransmitted.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a network management system according to the present invention. Since the basic configuration of this embodiment is the same as that shown in FIG. 3, the same parts are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, in the network management system of FIG. 3, the management device 1
In addition to the Trap response processing unit 16, a Trap response confirmation unit 27 and a Trap retransmission processing unit 28 are added to the managed device 2. Furthermore, MI
An object called TrapRetransmission is set in B26. Trap response processing unit 1
6 is T when the Trap processing unit 11 receives the Trap.
Set-Request to set Trap contents to object value of rapRetransmission
Is transmitted from the Set-Request transmission unit 15. The Trap response confirmation unit 27 uses the Trap
The elapsed time from the time when the Trap is transmitted from the transmission unit 21 is measured, and within a certain time, TrapRetransmi
It is for recognizing whether or not the Trap content transmitted is set to the object value of session.

The Trap resend processing unit 28 causes the Trap response confirmation unit 27 to set TrapRet within the fixed time.
T sent to the object value of the transmission
If it is recognized that the rap contents are not set,
The Trap transmission unit 21 is caused to execute the Trap transmission again.

FIG. 2 is a Trap transmission sequence showing the operation of the present embodiment. When the Trap transmission is normally performed, as shown in FIG. Trap transmission unit 2 when an event
Trap is transmitted from 1. At the same time, Trap
The response confirmation unit 27 measures the elapsed time after the Trap transmission. In the management device 1, the Trap transmission unit 21
Upon receiving the Trap transmitted from the trap response processing unit 16, the Trap response processing unit 16 causes the Set-Request transmission unit 15 to send the T
Set to set the received Trap contents for the rapRetransmission object
-Send a Request. This Set-Request
The managed device 2 that has received est receives Set-Request.
In the est processing unit 25, TrapRetransmissi
Set Trap contents to the object value of on. When this object is set, the Trap response confirmation unit 27 confirms that the set object value matches the already transmitted Trap contents, stops the elapsed time measurement, and sends the Get-Response message. The unit 22 transmits Get-Response.

However, in the case where the transmission of the Trap is not normally performed, as in the case where the transmitted Trap has disappeared on the network, as shown in FIG. Since the Set-Request is not returned from, the elapsed time exceeds the fixed time before the measurement of the elapsed time in the Trap response confirmation unit 27 is stopped. At this time, the Trap retransmission processing unit 28 causes the Trap transmission unit 21 to retransmit the Trap, and the same sequence is performed thereafter.

As described above, according to this embodiment, in the conventional network management system using SNMP,
The Trap response processing unit 16 is added to the management device 1, and the Trap response confirmation unit 27 and T are provided to the managed device 2.
TCP is added such that the rap retransmission processing unit 28 is added.
It is possible to add Tra without adding new programs such as
It was possible to secure the reliability of p transmission.

If the Trap contents are not set to the object value of TrapRetransmission even if the managed device 2 performs the retransmission processing by the Trap retransmission processing unit 28 for a certain number of times, the Trap contents are recorded as undelivered Trap information. A function of storing in a dedicated object prepared for this purpose may be added. In this way, the undelivered Trap remains as a record and can be confirmed later.

Further, in the present embodiment, the management device 1 which receives the Trap sends the Set-Request as a response to the managed device 2, but the Get-Request.
You may make it return st and Get-Next-Request. In this case, Tra of the managed device 2
In the p-retransmission processing unit 28, TrapRetransmis
Get-Requests for object of sion
If t, Get-Next-Request cannot be received within a fixed time, Tra is sent to the Trap transmission unit 21.
It is only necessary to retransmit p.

Also, the Set-Re sent by the management device 1
Target object name of quest is TrapRetra
Although it is set to nsmission, other object names may be used. Further, in FIG. 2, S of the management device 1
For the et-Request, the managed device 2 is Get-
I try to send a response, but Get
-The Response may not be transmitted.

In this embodiment, in the managed device 2, if the Trap response confirmation unit 27 does not set the Trap content to the object value of TrapRetransmission within a fixed time, the Trap resend processing unit 28 resends the Trap. I tried to do it, but Tra
Even if the p-retransmission processing unit 28 is not added, the managed device 2
By displaying the contents of the Trap on a device locally connected to the device, it is possible to provide the same function as the addition of the Trap retransmission processing unit 28.

[0022]

As described above, according to the first aspect of the present invention, the Trap response processing unit provided in the management apparatus causes the PDU relating to the specific management object when the Trap transmitted from the managed device is received. Is transmitted to the managed device, and the Trap provided in the managed device is transmitted.
The response confirmation unit makes it possible to recognize whether or not the PDU from the management device is received within a certain period after the Trap is transmitted, and when the PDU is not received, it is possible to know that the Trap transmission has failed. As a result, it is possible to provide a network management system that can secure the transmission reliability of Traps that a managed device transmits to a management device without increasing the memory capacity of the network constituent devices.

According to the invention of claim 2, in the invention of claim 1, the Trap further provided on the managed device.
By the re-transmission processing unit, the Trap response confirmation unit performs Trap
If it is found that the transmission of the
Since p is retransmitted, Trap can be transmitted reliably.

[Brief description of drawings]

FIG. 1 is a block diagram of a network management system showing an embodiment of the present invention.

FIG. 2 is a sequence diagram showing an operation of the above.

FIG. 3 is a block diagram of a conventional network management system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Management apparatus 2 Managed device 11 Trap processing part 12 Get-Response processing part 13 Get-Request transmission part 14 Get-Next-Request transmission part 15 Set-Request transmission part 16 Trap response processing part 21 Trap transmission part 22 Get-Resp. Transmission unit 23 Get-Request processing unit 24 Get-Next-Request processing unit 25 Set-Request processing unit 26 MIB 27 Trap response confirmation unit 28 Trap retransmission processing unit

Claims (2)

[Claims] 1. A management device that performs network management using SNMP and a managed device that is managed using SNMP, and sends a PDU called Trap when an event to be managed occurs from the managed device. In the network management system, the management device recognizes the content of the event by receiving the Trap.
The management device transmits to the Tr transmitted from the managed device.
When ap is received, a Trap response processing unit that transmits a PDU relating to a specific managed object to the managed device is added, and the managed device receives a trap from the management device within a certain period after transmitting the Trap. A network management system comprising a Trap response confirmation unit for recognizing whether or not a PDU has been received. 2. When the Trap response confirmation unit of the managed device recognizes that the PDU from the management apparatus has not been received within a certain period after the Trap is transmitted,
The network management system according to claim 1, further comprising a Trap resend processing unit that resends the Trap.